1. Field of the Invention
The present invention realtes to a plasma apparatus utilizing electron cyclotron resonance used as a CVD (chemical vapor deposition) apparatus, an etching apparatus, a sputtering apparatus or the like for manufacturing semiconductor equipments, and more particularly to a plasma apparatus using a specimen chamber in common with respect to two plasma generation chambers.
2. Description of the Prior Art
The plasma apparatus utilizing electron cyclotron resonance (to be hereinafter referred to as ECR) is advantageous in that plasma of high activity can be obtained under low gas pressure, the ion energy can widely be selected, a large ion current is obtained, and an ion flow is superior in directivity and uniformity, and has been promoted in research and development as the apparatus indispensable for manufacture of a high integrated semiconductor apparatus.
FIG. 1 is a longitudinally sectional view of the conventional plasma apparatus utilizing the ECR as the plasma CVD apparatus, in which a plasma generation chamber 31 is shown. The plasma generation chamber 31 is surrounded with double framed walls and provided therebetween with a cooling water flow chamber 31a, at the center of the upper wall with a microwave inlet 31c vacuum-sealed by a quartz glass plate 31b, and at the center of the lower wall with a plasma extraction window 31d opposite to the microwave inlet 31c. A wave guide 32 is connected at one end thereof with the microwave inlet 31c, a reaction chamber 33 as specimen chamber is provided and faces the plasma extraction window 31d, and exciting coils 34 are disposed around and coaxially with the plasma generation chamber 31 and an end portion of the wave guide 32 connected thereto.
The waveguide 32 is connected at the other end thereof with a high frequency oscillator (not shown), in the reaction chamber 33 is disposed a specimen table 36 for a specimen S of a semiconductor wafer or the like opposite to the plasma extraction window 31d, and an evacuation port 33a communicating with an evacuation system 37 is open at a lower wall of the reaciton chamber 33. In addition, reference numerals 31e and 31f designate a supply system for cooling water and a drain system therefor respectively and 31g designates a gas supply system.
In such plasma CVD apparatus, the specimen S is placed on the specimen table 36, gas is introduced into the plasma generation chamber 31 through a primary gas supply system 31g, D.C. voltage is applied to the exciting coils 34, and microwave power is introduced into the plasma chamber 321 through the wavguide 32, so that plasma is generated in the plasma generation chamber 31. The generated plasma is incident on the specimen S in the reaction chamber 33 by means of a divergent magnetic field generated by the exciting coils 34 and lowered of the magnetic flux density from the plasma extraction window 31d toward the reaction chamber 33 thereunder, thereby plasma-decomposing the gas in the reaction chamber 33 to form a semiconductor film or the like on the surface of the specimen S.
When semiconductor films are formed on many specimens by such the apparatus respectively, the plasma apparatus of course increases in number corresponding to the number of specimens. As a result, the problem is created in that it is much useless in equipment to increase the plasma apparatus independently and an installation space is liable to be wasted.